/Engine/Source/Runtime/Core/Public/Math/RangeSet.h
This method merges overlapping ranges into a single range (i.e. {[1, 5], [4, 6]} becomes [1, 6]). Adjacent ranges (i.e. {[1, 4), [4, 6)} are also merged.
void Add ( [RangeType](API\Runtime\Core\Math\TRange) Range )